[GHC] #5913: Type class dictionary call loops at runtime

[GHC]

#5913: Type class dictionary call loops at runtime
-----------------------------------------+----------------------------------
  Reporter:  mnislaih                    |          Owner:                  
      Type:  bug                         |         Status:  closed          
  Priority:  normal                      |      Milestone:  7.6.2           
 Component:  Compiler                    |        Version:  7.4.1           
Resolution:  fixed                       |       Keywords:                  
        Os:  Unknown/Multiple            |   Architecture:  Unknown/Multiple
   Failure:  Runtime crash               |     Difficulty:  Unknown         
  Testcase:  typecheck/should_run/T5913  |      Blockedby:                  
  Blocking:                              |        Related:                  
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Changes (by simonpj):

  * status:  new => closed
  * testcase:  => typecheck/should_run/T5913
  * resolution:  => fixed


Comment:

 Fixed by the silent-superclass patch.
 {{{
 commit aa1e0976055e89ee20cb4c393ee05a33d670bc5d
 Author: Simon Peyton Jones <simonpj at microsoft.com>
 Date:   Sun May 27 22:31:43 2012 +0100

     Add silent superclass parameters (again)

     Silent superclass parameters solve the problem that
     the superclasses of a dicionary construction can easily
     turn out to be (wrongly) bottom.  The problem and solution
     are described in
        Note [Silent superclass arguments] in TcInstDcls
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5913#comment:6>
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